Showing papers in "International journal of sustainable built environment in 2014"

Climate change and challenges of water and food security

Abstract: Water and food security are the key challenges under climate change as both are highly vulnerable to continuously changing climatic patterns. Studies have predicted that the average global temperature may increase by 1.4–5.8 °C and there would be substantial reduction in fresh water resources and agricultural yield by the end of the 21st century. Approximately 75% of the Himalayan glaciers are on retreat and will disappear by 2035. Moreover in Africa (Sub-Saharan Africa) by 2050 the rainfall could drop by 10%, which would reduce drainage by 17%. Majority of the fresh water resources has already been depleted and there is reduction in agricultural production globally with escalation in population and food demand. Some of the prominent climate change impacts are, growing deserts, and increase in the magnitude of floods and droughts. An extreme decline in crop yields in arid and semi arid areas globally has caused food shortages and a manifold increase in food inflation. Countries of Africa, Middle East, Arab and Asia have close economic ties with natural resource and climate-dependent sectors such as forestry, agriculture, water, and fisheries. This manuscript highlights groundwater recharge by utilization of wastewater using the Soil Aquifer Treatment (SAT) method in irrigation and the significance and methods of artificial recharge of groundwater. This paper also presents easily and economically feasible options to ensure water and food security under climate change and recommend formation of effective adaptation and mitigation polices and strategies to minimizing the impact of climate change on water resources and irrigation.

Modeling compressive strength of recycled aggregate concrete by Artificial Neural Network, Model Tree and Non-linear Regression

Abstract: In the recent past Artificial Neural Networks (ANN) have emerged out as a promising technique for predicting compressive strength of concrete. In the present study back propagation was used to predict the 28 day compressive strength of recycled aggregate concrete (RAC) along with two other data driven techniques namely Model Tree (MT) and Non-linear Regression (NLR). Recycled aggregate is the current need of the hour owing to its environmental friendly aspect of re-use of the construction waste. The study observed that, prediction of 28 day compressive strength of RAC was done better by ANN than NLR and MT. The input parameters were cubic meter proportions of Cement, Natural fine aggregate, Natural coarse Aggregates, recycled aggregates, Admixture and Water (also called as raw data). The study also concluded that ANN performs better when non-dimensional parameters like Sand–Aggregate ratio, Water–total materials ratio, Aggregate–Cement ratio, Water–Cement ratio and Replacement ratio of natural aggregates by recycled aggregates, were used as additional input parameters. Study of each network developed using raw data and each non dimensional parameter facilitated in studying the impact of each parameter on the performance of the models developed using ANN, MT and NLR as well as performance of the ANN models developed with limited number of inputs. The results indicate that ANN learn from the examples and grasp the fundamental domain rules governing strength of concrete.

Role of lime with cement in long-term strength of Compressed Stabilized Earth Blocks

Abstract: Compressed Stabilized Earth Blocks (CSEBs) are manufactured using stabilizers to provide adequate compressive strength and durability, so, as to make them suitable as building blocks. Though cement is a popular stabilizer used in manufacture of CSEBs, no study has been reported utilizing lime in combination of cement. This experimental study on CSEBs prepared using lime as a replacement to cement in certain proportions has clearly brought out the effectiveness of lime with cement in improving the long-term build-up of strength better than using cement alone. It was observed that blocks prepared with optimum quantity of lime along with cement has led to continuous buildup of strength even beyond 2 years, whereas blocks prepared with cement alone and lesser quantity of lime than optimum quantity have not gained much strength after 6 months from the time of preparation of the blocks. The research findings show a need to relook at the grading of ingredients and quantity of stabilizers for achieving good building blocks. This would be an added benefit not only in reducing the cost of the blocks, but also has serious implications in terms of the reduction of energy consumed in the manufacture of blocks when done in large scale.

A comprehensive study of green roof performance from environmental perspective

Abstract: Green roofs have been established for over 100 years and they have been become one of the key elements in urban area in the past few decades. Many scientific researches focus on its cooling performance, efficiency and survival rates of plants. This article provides an overview mainly from two aspects, the vegetation on the green roofs and its benefits toward the surrounding environments. Vegetation is the key element in installing green roofs. It also provides some factors in choosing suitable plants on rooftops, factors including species that are drought tolerant, solar radiation tolerant, and cooling ability of plants. In addition, green roofs play a critical role in improving the urban environment by enriching the biodiversity, delaying the storm peak to the drainage system, diminishing the runoff quantity, purifying the air pollutants as well as the runoff quality.

Carbon footprint and embodied energy consumption assessment of building construction works in Western Australia

Abstract: The Australian Green Infrastructure Council (AGIC) is currently leading a new approach to the delivering and operating of infrastructure through a more careful examination of the carbon footprint of construction activities. Using a life cycle assessment (LCA) methodology, this paper presents life cycle greenhouse gas (GHG) emissions and energy analysis of the Engineering Pavilion (hereinafter referred to as Building 216), at Curtin University Western Australia. The University utilises a Building Management System (BMS) to reduce its overall operational energy consumption. This LCA analysis employed a ‘mining to use’ approach, in other words, the analysis takes into account all of the stages up to the utilisation stage. The life cycle GHG emissions and embodied energy of Building 216 were calculated to be 14,229 tonne CO2-e and 172 TJ, respectively. This paper identified the ‘hotspots’, or the stages in production and operation of Building 216 that were the cause of the majority of the GHG emissions. From this, proposals for further improvements in environmental management may be made. The usage stage of the building produces 63% less GHG emissions than the University average, due to the implementation of the BMS. This system has played a significant role in reducing the total embodied energy consumption of the building (i.e., 20% less than the University average).

Criteria for the selection of sustainable onsite construction equipment

Abstract: Today’s construction projects are highly mechanized and becoming more so every day. With the growing industrialization of construction work, the role of onsite equipment and machineries is vital in achieving productivity and efficiency. During the construction phase, selection of right equipment has always been a key factor in the success of any construction project. This decision is typically made by matching equipment available in a fleet with the tasks at hand. Such analysis accounts for equipment productivity, equipment capacity, and cost. However, the emerging notion of sustainability in construction has emphasized energy conservation, efficiency, green environment, economy and human well being. In this context, selecting the most appropriate equipment from the available options is highly challenging. Therefore, this paper aims to determine a selection criteria based on the fundamental concept of sustainability and provides an assessment framework. A questionnaire survey was conducted among a classified group of Malaysian contractors to elicit information pertaining to the sustainable selection of onsite machineries. The findings of this study will guide the decision makers to appraise the selection process of construction equipment on the triple bottom line of sustainability.

Impacting Sustainable Behavior and Planning in Smart City

Abstract: In recent literature, the concepts of smart, intelligent or cognitive cities have gained increasing attention as approaches for addressing the challenges of urban management. In smart city by having the right information at the right time, citizens, service providers, and city government will be able to make better decisions to increase quality of life for urban residents and the overall sustainability of the city. It is therefore stipulated that information resulting from a smart city implementation has a two-fold impact: 1) it changes the social behavior of citizens towards more efficient and sustainable utilization of city resources (bottom-up) and 2) it allows service providers (such as utilities and transit companies) and the city government to provide more efficient and sustainable services (top-down). There is an explicit need to understand the impacts of smart cities on urban environmental, social and economic sustainability from a holistic perspective. In this paper, we will use conceptual systems diagrams to map the different aspects of this relationship as outlined in the literature and identify the gaps that will need to be addressed to robustly understand the full impact of smart cities on the above-mentioned dimensions of urban sustainability.

A review of Critical Project Management Success Factors (CPMSF) for sustainable social housing in Nigeria

Abstract: Purpose: The purpose of the study is to investigate and establish the Critical Project Management Success Factors (CPMSF) for the sustainable social (public) housing estates’ delivery/provision in Nigeria. The current housing estate deficit faced in the country is credited to poor and inadequate housing delivery and provision by various agencies. Method/design: Documentary analysis of data collection was used in the study which involved an extensive and investigative theoretical review of online and visual document resources, followed by an interpretative identification of categories and limits of various materials and information considered vital to the phenomenon in the study. The documents were analysed with a content analysis approach under four criteria of how: authentic; credible; representative; and meaningful. Findings/results: The study reveals that 22 Critical Project Management Success Factors (CPMSF) are essential for the achievement of sustainable social (public) housing estates’ delivery/provision in Nigeria. These relate to: the project managers’ performance; the organisation that owns the development project; the characteristics of the team members; and the external project environment. At the same time, the study reveals that these are social, economic, and environmental factors that are associated with the triple objectives of sustainable development. Originality/value: This study reflection aims to resolve or reduce to a minimum the acknowledged housing estate delivery and provision inadequacy problems in the country, and by exploring this phenomenon, best practise project management techniques will be understood and used to provide sustainable social (public) housing estate units for the Nigerian populace.

Selecting the most efficient genetic algorithm sets in solving unconstrained building optimization problem

Abstract: Effective optimization of unconstrained building optimization problem involves coupling a building energy simulation program with an optimization evolutionary algorithm such as the genetic algorithm (GA). The aim of this paper is to find the most appropriate GA set that obtains the optimum, or near optimum, solutions in a reasonable computational time (less numbers of simulations). Twelve control parameter sets of binary encoded GA are tested to solve unconstrained building optimization problems that are coupled with EnergyPlus simulation program. The results show that population size is the most significant control parameter and that the crossover probability and mutation rate have insignificant effects on the GA performance. In general, a binary encoded GA with small population sizes can be used to solve unconstrained building optimization problems by around 250 building simulation calls. In particular, the smaller population size of about 5 individuals helps reach the optimum solution faster than larger population sizes.

Indoor pollution from solid biomass fuel and rural health damage: A micro-environmental study in rural area of Burdwan, West Bengal

Abstract: Emissions from biomass combustion are a major source of indoor and outdoor air pollution, and are estimated to cause millions of premature deaths worldwide annually. In this study, we assessed the effect of exposure to biomass smoke on various health status including blood pressure, gaseous component and ventilation pattern of kitchen and living room. For this investigation, a number of measurements were done to obtain indoor air quality (IAQ) data (indoor humidity, temperature, CO, CO2 and O3 concentration). Blood pressure was measured at baseline and one hour post-exposure. Results highlighted that a higher concentration of CO2 was released during burning of dry leaf, straw, cow dung compared to that from straw and LPG gas. Moreover, correlation study showed a strong negative relationship between CO and humidity (r = −0.609, p

Emergy-Based Life Cycle Assessment (Em-LCA) of Multi-Unit and Single- Family Residential Buildings in Canada

Abstract: The construction and building process depends on substantial consumption of natural resources with far-reaching impacts beyond their development area. In general, a significant portion of annual resource consumption by the building and construction industry is a result of applying traditional building strategies and practices such as designing and selecting types of development (e.g. multi-unit condo and single-family house, etc.), building materials and structure, heating/cooling systems, and planning renovation and maintenance practices. On the other hand, apart from structural suitability, building developers mostly consider the basic requirements of public owners or private occupants of the buildings, where the main criteria for selecting building strategies are costs, and long-term environmental and socio-economic impacts are generally ignored. The main purpose of this paper is to develop an improved building sustainability assessment framework to measure and integrate different sustainability factors, i.e. long-term environmental upstream and downstream impacts and associated socio-economic costs, in a unified and quantitative basis. The application of the proposed framework has been explained through a case study of single-family houses and multi-unit residential buildings in Canada. A comprehensive framework based on the integration of emergy synthesis and life cycle assessment (LCA) has been developed and applied. The results of this research prove that the proposed emergy-based life cycle assessment (Em-LCA) framework offers a practical sustainability assessment tool by providing quantitative and transparent results for informed decision-making.

New model to estimate and evaluate the solar radiation

Abstract: This research work proposed a new model used to predict the direct, diffuse and global solar flues for clear skies, by making the comparison between the numerical simulation of this model and the climatology measured data of Energetic Laboratory station the Faculty of science of Tetouan city (35.57361 latitude, −5.37528 longitude) in Northern Morocco. The results indicate that the proposed model can be successfully used to estimate the solar radiation during all the seasons of year for studied position and for considered day, using as input the altitude (degrees), longitude (degrees) and latitude (m).

Life cycle cost and carbon footprint of energy efficient refurbishments to 20th century UK school buildings

Abstract: This study presents a method for assessing energy efficient refurbishment options for schools in the UK. The method accounts for life cycle effects on cost and carbon emissions since refurbished buildings will last for many years. Four schools are identified as representative of school archetypes built in the UK during four distinct periods in the 20th century. The schools are used as a base for simulation of the effects of energy efficient refurbishment of building fabric and heating plant. All possible combinations of the selected measures are simulated. Simulated energy savings are then compared between the four school buildings, demonstrating how physical characteristics of the schools affect the available savings. Simulating combinations of energy efficiency measures allow analysis of interaction effects between measures, and reveals some positive and some negative interactions. A regression model of energy savings in the four schools is also developed. Simulated energy savings are then used as inputs for a life cycle assessment model. Life cycle indicators considered are marginal life cycle cost and marginal life cycle carbon footprint. These metrics are used to rank the energy efficiency measures on net present value and life cycle carbon footprint saving, both individually and in combination with each other. Carbon payback is shorter than financial payback in all scenarios, and all measures and combinations of measures repaid the carbon invested in them. Positive net present value is less common, and frequently depends on air tightness improvements also being achieved.

Approaches to reducing carbon dioxide emissions in the built environment: Low carbon cities

Abstract: The interactions between water, energy, and food in terms of economic and environmental outcomes under conditions of a changing climate are something that all countries will need to understand if they intend to effectively manage the consequences. Qatar’s measures to increase food security and diversification of the energy system and economy can provide valuable insights to other countries with similar climates but who have a lower capacity to respond. Through Qatari-based organisations, best practice reflecting local characteristics can be shared throughout the region and beyond. The aim of this paper is to arrive at projections of CO 2 emissions in new cities in Qatar by 2020 using GSAS standards under a number of scenarios coupled with specific interventions that help them meet national and regional targets. The estimated CO 2 equivalent savings were calculated using GSAS energy calculator and based on the total area of the registered project and anticipated projects provided by different entities applying GSAS in Qatar. The projected annual savings of CO 2 emissions due to energy use reduction can be realised by 2020 when projects planned or under construction are completed. The projected CO 2 emission reduction is reported and compared with the international standards.

Dilemma of green and pseudo green architecture based on LEED norms in case of developing countries

Abstract: Achieving sustainable and eco-friendly architecture is one of the main objectives that humans for creating a better life have made as the ultimate model for all their professional activities. For this reason, moving towards a greener architecture is considered the main goal of the contemporary architecture of our time. The goal of this study is to analyse architectural projects that have been already performed in the Middle East countries in terms of their compatibility with actual concepts of sustainability and their required green criteria. Therefore, for the sake of review and study, this paper is intended to discover up to what level the sustainability rating system such as LEED (Leadership in Energy and Environmental Design) can be effective in rating contemporary architectural projects. Studies indicate three concepts for analysing contemporary architecture and have found to be descriptive: (1) green, (2) pseudo green and (3) energy-monger. The studies have also shown that some of the projects, although trying to display sustainable architecture concepts in appearance, in reality they turned out not to be sustainable enough. In latter steps, this paper intends to evaluate and examine the effectiveness of the LEED rating system. In evaluating LEED rating system, the results inferred indicate that the system is intended more for programming than actual designing purposes and is not an efficient instrument for analysing architectural design process. Analysis based on this study suggests that, for moving from pseudo green to green architecture, it is necessary to use design-oriented patterns.

Barriers to green buildings at two Brazilian Engineering Schools

Abstract: The objective of this short communication is to identify and analyze the main barriers to the adoption of green buildings at two traditional Schools/Colleges of Engineering in the state of Sao Paulo, Brazil The methodological process employed is the multiple case studies used to diagnose the main barriers to installing green buildings in these two cases The intention, of the institutions, to adopt greener buildings has been observed, considering the commitment of top management and that the institutions have put forth to accelerate this greening process However, the barriers to adoption are evident, especially those of a technical and cultural origin Based on these results, the study proposes possible solutions and guidelines to overcome such barriers, aimed at facilitating the adoption of green technologies in the buildings at Higher Education Institutions (HEIs)/Schools/Colleges of Engineering

Derivation of new design rainfall in Qatar using L-moment based index frequency approach

Abstract: For stormwater system design, flood estimation and many other environmental assessment tasks, design rainfall is an essential input. Estimation of design rainfall is generally made using a regionalization technique based on a regional database of observed rainfalls. Many countries have derived their own generalized design rainfall data, which are generally expressed in the form of intensity–duration–frequency (IDF) curves. In Qatar, situated in an arid region, the existing IDF data were developed in 1991 using a limited data set. This paper presents the development of new IDF data for the State of Qatar using the method of L-moments and the index regional frequency analysis approach. The daily rainfall data from 32 stations located in Qatar and nearby Gulf countries have been used to form a homogeneous region. It has been found that the Pearson Type 3 distribution best fits the 24-h duration annual maximum rainfall data in the Qatar region. For the ungauged case, a prediction equation is developed where mean annual maximum rainfall is expressed as a function of climatic and physiographic characteristics. From a leave-one-out validation, it has been found that the developed prediction equation can estimate mean annual maximum rainfall with a median relative error of about 5.5%. Finally, an approximate method is used to obtain design rainfalls for other durations due to the limitations of continuous pluviograph data in Qatar. The new set of IDF curves is based on a much bigger dataset than the existing 1991 IDF curves. It is expected that the new IDF curves will have wider application in Qatar and will provide a statistically sound basis for storm water design, flood and environmental studies. The method can be applied to other middle-eastern states and similar arid countries in the world.

Introduction of public bus transit in Indian cities

Abstract: Introducing public bus transit system in Indian cities raises many challenging issues of different nature ranging from technical to operational. The present study examines the impact of a new public bus transit system by applying a binary logit analysis for assessing the possible variation in modal shift behavior. The case study of mode-choice was developed, calibrated, and validated using socio-economic data collected on six proposed corridors in the city of Bardoli, Gujarat, India. Traffic quality parameters, such as average speed, delay, congestion, travel time, and travel cost were modeled to investigate the impact of the new bus transit system in VISSIM environment. The probability of an overall modal shift to proposed bus transit system corridors ranges from 45% to 51%. The maximum modal shift ranges from 80.58% to 87.40% for three-wheelers (para-transit) followed by bicycle and walking mode. However, cars have the least modal shift ranging from 6.78% to 11.49% and 37.38% to 45.46% for two-wheelers. The average speed of the bus transit system in both directions could reach 47.75–49.59 kmph with 15 min frequency. Likewise, mean travel time was estimated from 1.3 to 1.6 min per km and average commuter cost of less than Rs. 1.0 per km for bus transit with insignificant delay and congestion. Introduction of the new public bus system shows promising results and has to play a significant role in developing a sustainable urban public transportation system. These findings can be used to form the basis for the implementation of the new public bus transit in peer cities with relatively similar sizes, which may impact an inhabitant sustainable choice on ridership in due course.

Digital surface model based on aerial image stereo pairs for 3D building

Abstract: There is an increasing demand for 3D city models for many applications and users worldwide. Fez is one of the most important tourism locations in Morocco and is a challenge for 3D city modeling due to its complex buildings and road structure. Due to its importance this Historic Medina of Fez was added to the UNESCO World Heritage List in 1981. It is located in the northern part of Morocco. In this work, we discuss the construction of a digital surface model based on aerial image stereo pairs using matching method and the use of this DSM for 3D city planning. We used aerial photographs with high accuracy (1/4000) covering the study area acquired in 2007 and additional cartographic data from Fez. 3D land use zoning allowed building volumes, usage, and density. They are the main tools defining the image of a city and bring into focus the model of best practice of the rehabilitation and conservation of the historic Medina.

Conceptualisation and pilot study of shelled compressed earth block for sustainable housing in Nigeria

Abstract: Meeting the housing needs in Nigeria is a long-standing task, yet to be realised. The economy of the country, as most developing countries, is ailing with limited resources. Energy and infrastructures are inadequate, yet the use of cement dominated the construction industry. Earth construction is a sustainable option to housing with inherent characteristics that should be desirable in the ailing economy of hot tropical environment in Africa. However, most Nigerians are skeptical of taking a low cost option with less modern effects and uncertain durability. This research explores the issues relating to this problem and aims to bridge the gap between Nigerians and earth, which exists in abundance in Africa. The emerging concept from the survey of public reaction to earth construction in Nigeria is of a shelled compressed earth block (SCEB) of an inner core of ‘earth’ with less stabilisation and an outer shell of the same earth composition but with higher ratio of cement stabilisation for adequate durability, compressed into a single piece. A mechanical kit was designed and fabricated for the production of sample shelled compressed earth block for laboratory tests. Basic preliminary tests were conducted on the model and results revealed that the concept was feasible thus paved the way for further research work in shelled compressed earth block (SCEB).

Vulnerability of bus and truck drivers affected from vehicle engine noise

Abstract: The purpose of this study was to find out the vulnerability of bus and truck drivers due to constant exposure of vehicle-engine noise inside the vehicle cabin. Comparative results revealed that noise levels inside the cabin of buses and trucks were in the range of 88.6–102.4 dB and 87.95–103.4 dB, respectively. The health status of bus and truck drivers was assessed by measuring their systolic and diastolic pressure, pulse rate, BMI, digestion problem, hearing loss, vision problem, back pain and irritation. Paired t-test of the results revealed non-significant (p

Use of local discarded materials in concrete

Abstract: Steel slag, a by-product of steel manufacturing, is generated in large quantities in Qatar. In fact, it is estimated that more than 400,000 tons of steel slag are generated annually in the country. Gravel, resulting from washing sand, is also produced at more than 500,000 tons/year in Qatar. Both materials are not efficiently used in the country and most of its aggregate (gabbro) needs are imported from neighboring countries. This paper presents the results obtained on the use of steel slag, gravel and gabbro in concrete. A total of nine concrete mixtures were prepared. One concrete mixture that contained 100% gabbro aggregate was considered as the control mix. Four concrete blends containing 100%, 75%, 50%, and 25% steel slag (by weight) were prepared as partial replacements of gabbro aggregates. Another four concrete mixtures containing 100%, 75%, 50%, and 25% gravel (by weight) were cast as partial replacements of gabbro aggregates. All samples were cured in a water tank for 7, 28 and 90 days and then subjected to compressive, flexural and splitting tensile strength tests. All concrete mixtures prepared easily met the 28-day compressive strength design requirement of 28 MPa. Best results were obtained for concrete prepared using 100% steel slag aggregates. Concrete cast using 100% gravel yielded lower strength results than the control mixture (100% gabbro). However, there was an increase in strength values with an increase in gabbro content in gravel/gabbro mixtures. Additional work is necessary to establish long-term performance, especially concerning what is reported in the literature about the expansive characteristics of steel slag aggregates when used in concrete. It should be noted that concrete cured for 90 days in the water tank did not exhibit any reversal in strength.

Integrating a fuzzy-logic decision support system with bridge information modelling and cost estimation at conceptual design stage of concrete box-girder bridges

Abstract: Integrating 3D bridge information modelling (BrIM) with construction technologies had inspired many researchers for the past decade. In this study, research objectives are intended to demonstrate the viability of integrating a 3D computer-aided design (3D-CAD) model with a structural analysis application and bridge cost estimation framework without compromising interoperability matters. An integrated model that relates a fuzzy logic decision support system with cost estimation for concrete box-girder bridges is presented. Model development methodology comprises an integrated preliminary cost estimation system (IPCES), and complex quality functions and deployment of a multi-criteria decision making (MCDM) approach. An actual case project is used to validate and illustrate model corresponding estimating capabilities. The proposed model is engineered to enhance existing techniques implemented by bridge stakeholders and designers to prepare cost estimates at the conceptual design stage by taking into consideration box-girder bridge project site preparations, substructure, and superstructure. The proposed model is anticipated to be of major significance to designers and its contribution resides into the integration of BrIM technologies with cost estimation approaches.

Assessing the trend in rental values of commercial properties along oyemekun road akure, nigeria

Abstract: Commercial property investment which is now very evident along Oyemekun Road, Akure, Nigeria, a place characterized hither to with residential development leaves investors at dark with the choice of commercial property investment. The commercial properties evident in the study area are Purpose-built office space, Converted office space and Shopping Complex. In a bid to lead investors aright on the best decision of the type of property to invest their hard earned income in, there was the study of the trends in rental values of the properties between 2006 and 2011 in order to discover that with the highest trend. This study which is a cross-sectional research that entailed the survey of the entire 22 Estate Surveying Firms in the study area made use of questionnaires as the primary source of data. There was also the use of both descriptive and inferential statistical techniques such as the frequency distribution table and the simple linear regression, and Analysis of Variance (ANOVA). From the study it was also revealed that although purpose built office space with the highest R 2 of 0.9 having the highest trend in rental values will result to a faster recoup of investment, the converted office space is most evident (53%) while the shopping complex is the most professionally managed (46%) respectively. The use of (ANOVA) coupled with Tukey post-hoc test reveals that the rental values of the three properties at the 95% confidence level are significantly different (p=0.000). The researchers therefore opines that the purpose built office space commanding the highest rent and trend should be the focus of both investors and even professional managing agents in order to maximize returns.

An academic goal of socio-ecological sustainability: A comprehensive review from a millennial-scale perspective

Abstract: We introduce the concept of millennial-scale sustainability as part of an academic approach to solving various technological problems faced by humans in modern society and for managing scientific technology. We further discuss the rationale behind the application of such a sociological concept to science. First, we compare the value of having a relatively short-term outlook (corresponding to the human life span) on the relation between technology and human activities to a 1000-year outlook by considering the correlation between our current situation and past technology, taking note of the scientific and technological policies, and human activities of the past 1000 years. In particular, we discuss the relationship between human activities and environmental issues. The problem is not one of current sustainability but, rather, of future sustainability. Therefore, the importance of applying the 1000-year outlook to the technology used in various applications is emphasized. Second, by looking back 1000 years, we discuss the realization of existing technology over that period. Examples of sustainable scientific technology from the past 1000 years are given, including the importance of artificial structures and new computer systems. Third, solving global environmental problems, including the supply of and demand for food, mitigation of climate change, and the response to natural disasters is an important concern of scientists in the 21st century, and is aided by simulations that include comprehensive historical investigations of civilizations that unify both natural and anthropogenic systems to define 1000-year sustainability scientific technology. The concept of 1000-year sustainability will move from sustainable development to sustainability development or the development of sustainability, which is the goal of a continuous society.

Assessment of Environmental Responses to Land use/Land cover Dynamics in the Lower Ogun River Basin, Southwestern Nigeria. Abstract

Abstract: This study investigated the pattern of land use/land cover change in the Lower Ogun River Basin between 1984 and 2012. Two sets of topographical map, a LandSat-5 TM image of 1984, LandSat-7 ETM+ of 2000 and a Google Earth image of 2012 were used for the study. The topographical maps and satellite images were digitally processed using ILWIS 3.2 software and exported to ArcGIS 9.3 for further processing and analysis. The processed images were subsequently classified using the maximum likelihood classification algorithm, resulting in the identification of seven land use classes, which are, farmland, forested wetland, light forest, non-forested wetland, shrub, urban and water body. Furthermore, change detection analysis was carried out using the cross module of the ILWIS software. The result of the change detection analysis indicated that between 1984 and 2000, 80.08 % of the land cover in the area has been converted to other land uses while only 19.92 % remained unchanged. Also within the same period, light forest, non-forested wetland and forested wetland decreased at average rates of 8.26, 4.66 and 2.81 (%) per annum respectively, while water body also decreased at an annual rate of 0.17 %. On the other hand farmland, shrub and urban/built-up areas expanded at average rates of 7.23, 6.74 and 4.65 (%) respectively. The result further indicated that between 2000 and 2012 49.86 % of the land cover has been converted to other land uses, while 50.14% remained unchanged, and that farmland, shrub, urban/built-up and forested wetland, expanded at average rates of 6.01, 1.95, 0.89 (%) and 0.17 % per annum respectively, just as Light forest, non-forested wetland and water body decreased by 8.26, 2.70 (%) and 1.40 % annually. Five composite soil samples each to the depth of 0-20 cm were randomly collected and analyzed for their physicochemical properties using standard methods to determine the impact of land use/land cover change on soil quality in the selected forested and non-forested wetlands. The findings have shown the growing impacts of urban agriculture on the wetland ecosystem within the study area; resulting in soil degradation and biodiversity loss. The implication of these findings is that the area is made to be susceptible to devastating flooding which can culminate in the loss of lives and properties. The study therefore recommended the development of effective land management information system and policies that will ensure sustainable management of fragile ecosystem. Keywords : change detection, river basin, urban agriculture, land use/land cover, satellite images, soil degradation, Wetlands. Normal 0 false false false EN-GB X-NONE X-NONE